Exchange (SwitchYard: Javadoc 2.0.1.redhat-621084 API)

```
public interface Exchange
```
An Exchange represents an instance of a service invocation with a specific message exchange pattern (e.g. InOnly, InOut). Exchange provides a conduit for the messages that flow into and out of a service as part of a service invocation. Unlike messages, an exchange cannot be copied and reused across service invocations. State associated with an invocation (i.e. context) is maintained at the exchange level.

Field Summary

Fields
Modifier and Type	Field and Description
`static String`	`CONTENT_TYPE` Context property name used for Message Content Type.
`static String`	`FAULT_TYPE` Context property name used for Fault Type.
`static String`	`MESSAGE_ID` Context property name used for Message ID.
`static String`	`OPERATION_NAME` Context property name used for Operation Name.
`static String`	`PROPAGATE_EXCEPTION_ON_IN_ONLY` Domain property name used for a boolean flag which indicates if the exception should be propagate back to the service consumer.
`static String`	`RELATES_TO` Context property name used for Relates To.
`static String`	`ROLLBACK_ON_FAULT` Context property name used for A boolean flag which indicates if the transaction should be rolled back or not on fault.
`static String`	`SERVICE_NAME` Context property name used for Service Name.

Method Summary

Methods
Modifier and Type	Method and Description
`Exchange`	`consumer(ServiceReference consumer, ServiceOperation operation)` Set service consumer info for this exchange.
`Message`	`createMessage()` Create a message to be used with this exchange.
`ServiceReference`	`getConsumer()` Get the service reference representing the consumer.
`Context`	`getContext()` Retrieves the exchange context.
`Context`	`getContext(Message message)` Retrieves context available for passed message.
`ExchangeContract`	`getContract()` The contract between consumer and provider for this exchange.
`Message`	`getMessage()` Returns the current message for the exchange.
`ExchangePattern`	`getPattern()` Provides the consumer's view of the message exchange pattern.
`ExchangePhase`	`getPhase()` Get the exchange phase.
`Service`	`getProvider()` Get the service representing the provider.
`ExchangeHandler`	`getReplyHandler()` Get the reply handler for this exchange.
`ExchangeSecurity`	`getSecurity()` Get the exchange security.
`ExchangeState`	`getState()` Get the exchange state.
`Exchange`	`provider(Service provider, ServiceOperation operation)` Set service provider info for this exchange.
`void`	`send(Message message)` Sends the specified message as part of this message exchange.
`void`	`sendFault(Message message)` Sends the specified message as part of this message exchange.

- Field Detail
  - MESSAGE_ID
```
static final String MESSAGE_ID
```
    Context property name used for Message ID.
    
    See Also:
    Constant Field Values
  - RELATES_TO
```
static final String RELATES_TO
```
    Context property name used for Relates To.
    
    See Also:
    Constant Field Values
  - CONTENT_TYPE
```
static final String CONTENT_TYPE
```
    Context property name used for Message Content Type.
    
    See Also:
    Constant Field Values
  - OPERATION_NAME
```
static final String OPERATION_NAME
```
    Context property name used for Operation Name.
    
    See Also:
    Constant Field Values
  - FAULT_TYPE
```
static final String FAULT_TYPE
```
    Context property name used for Fault Type.
    
    See Also:
    Constant Field Values
  - SERVICE_NAME
```
static final String SERVICE_NAME
```
    Context property name used for Service Name.
    
    See Also:
    Constant Field Values
  - ROLLBACK_ON_FAULT
```
static final String ROLLBACK_ON_FAULT
```
    Context property name used for A boolean flag which indicates if the transaction should be rolled back or not on fault.
    
    See Also:
    Constant Field Values
  - PROPAGATE_EXCEPTION_ON_IN_ONLY
```
static final String PROPAGATE_EXCEPTION_ON_IN_ONLY
```
    Domain property name used for a boolean flag which indicates if the exception should be propagate back to the service consumer.
    
    See Also:
    Constant Field Values
- Method Detail
  - getContext
```
Context getContext()
```
    Retrieves the exchange context.
    
    Returns:
    the exchange context
  - getContext
```
Context getContext(Message message)
```
    Retrieves context available for passed message. If message is same as message available on this exchange it will return same context as getContext() method, otherwise another instance of Context will be returned.
    
    Parameters:
    message - Message instance.
    
    Returns:
    Context for message.
  - getConsumer
```
ServiceReference getConsumer()
```
    Get the service reference representing the consumer.
    
    Returns:
    The consumer service reference instance.
  - getProvider
```
Service getProvider()
```
    Get the service representing the provider. This method will return null before an exchange is sent for the first time.
    
    Returns:
    the provider's service
  - getContract
```
ExchangeContract getContract()
```
    The contract between consumer and provider for this exchange.
    
    Returns:
    exchange contract
  - consumer
```
Exchange consumer(ServiceReference consumer,
                ServiceOperation operation)
```
    Set service consumer info for this exchange.
    
    Parameters:
    consumer - the service reference used by the exchange
    operation - the operation being invoked
    
    Returns:
    this Exchange instance
  - provider
```
Exchange provider(Service provider,
                ServiceOperation operation)
```
    Set service provider info for this exchange.
    
    Parameters:
    provider - the service provider used by the exchange
    operation - the operation being invoked
    
    Returns:
    this Exchange instance
  - getMessage
```
Message getMessage()
```
    Returns the current message for the exchange. On new exchanges, this method will always return null. The current message reference is updated with each call to send().
    
    Returns:
    the current message for the exchange
  - createMessage
```
Message createMessage()
```
    Create a message to be used with this exchange.
    
    Returns:
    new message
  - send
```
void send(Message message)
```
    Sends the specified message as part of this message exchange.
    Implementations must throw an IllegalStateException if this method is called when the Exchange state is in ExchangeState.FAULT.
    
    Parameters:
    message - message to send
  - sendFault
```
void sendFault(Message message)
```
    Sends the specified message as part of this message exchange.
    Also sets the Exchange state to ExchangeState.FAULT.
    
    Parameters:
    message - message to send
  - getState
```
ExchangeState getState()
```
    Get the exchange state.
    
    Returns:
    The exchange State.
  - getPhase
```
ExchangePhase getPhase()
```
    Get the exchange phase.
    
    Returns:
    the exchange phase
  - getReplyHandler
```
ExchangeHandler getReplyHandler()
```
    Get the reply handler for this exchange.
    
    Returns:
    reply handler
  - getPattern
```
ExchangePattern getPattern()
```
    Provides the consumer's view of the message exchange pattern. This method is equivalent to getContract().getConsumerOperation().getExchangePattern(). Note that if consumer information has not been set, this method will return null!
    
    Returns:
    the consumer's exchange pattern or null if no consumer info is set on the exchange
  - getSecurity
```
ExchangeSecurity getSecurity()
```
    Get the exchange security.
    
    Returns:
    the exchange security

Interface Exchange

Field Summary

Method Summary

Field Detail

MESSAGE_ID

RELATES_TO

CONTENT_TYPE

OPERATION_NAME

FAULT_TYPE

SERVICE_NAME

ROLLBACK_ON_FAULT

PROPAGATE_EXCEPTION_ON_IN_ONLY

Method Detail

getContext

getContext

getConsumer

getProvider

getContract

consumer

provider

getMessage

createMessage

send

sendFault

getState

getPhase

getReplyHandler

getPattern

getSecurity